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• Attractive toxic sugar baits (ATSBs) lure mosquitoes to feed on the baits. • Mosquitoes exposed to the ATSB solution for 48 h were killed within 7d. • A significant reduction of ovitrap density index (24 %) on isolated ATSB farms. • The intervention efficacy on nonisolated ATSB farms had mixed results. • Deploying simple ATSB stations is a practical approach for IVM programs. Attractive toxic sugar baits (ATSBs) lure mosquitoes to feed on the baits and subsequently killed them. We investigated the effects of a boric acid–containing ATSB on the population of Aedes albopictus at 48 h exposure and assessed the field effectiveness on this ATSB on two types of community farms in New Taipei City, Taiwan, including isolated ATSB farms and nonisolated ATSB farms. The result showed that mosquitoes exposed to the ATSB solution for 48 h were killed within 7 d under laboratory conditions. Exposure of female and male mosquitoes to ATSB resulted in mean survival times ranging from 52 to 62 h and 30 to 48 h, respectively. For field efficacy test, on isolated ATSB farms, a significant reduction of ovitrap density index (ODI) up to 24 % was noted after the replacement frequency was increased to every 2 weeks. However, the intervention efficacy on nonisolated ATSB farms had mixed results. The ODI significantly reduced by 21.4 % and 6.9 % on the nonisolated ATSB Chongmin and Nanjing farms, respectively, when bait replacement was done every 2 weeks instead of every 3 weeks. By contrast, the ODI on the nonisolated ATSB Yongchang farms increased significantly, irrespectively of the bait replacement frequency. Nevertheless, the total number of eggs trapped on all ATSB farms exhibited a concave curve pattern; while the mosquito population on non-ATSB control farms continued to increase over time. In conclusion, deploying simple ATSB stations containing boric acid is a practical approach for integrated vector management programs. [ABSTRACT FROM AUTHOR]

Aedes albopictus (Diptera: Culicidae) is a major vector of multiple diseases. While vaccines have been developed, preventing these Aedes- borne diseases continues to primarily depend on monitoring and controlling the vector population. Despite increasing research on the impacts of various factors on Ae. albopictus population dynamics, there is still no consensus on how meteorological or environmental factors affect vector distribution. In this study, the relationships between mosquito abundance and meteorological and environmental indicators were examined at the town level based on data collected from July to September, the peak abundance period of 2019 in Shanghai. In addition to performing Poisson regression, we employed the geographically weighted Poisson regression model to account for spatial dependency and heterogeneity. The result showed that the environmental factors (notably human population density, the Normalized Difference Vegetation Index (NDVI), socioeconomic deprivation, and road density) had more significant impacts than the meteorological variables in accounting for the spatial variation of mosquito abundance at a city scale. The dominant environmental variable differed in urban and rural places. Furthermore, our findings indicated that deprived townships are more susceptible to higher vector densities compared to non-deprived townships. Therefore, it is crucial not only to allocate more resources but also to increase attention towards controlling the vectors responsible for their transmission in these townships. [ABSTRACT FROM AUTHOR]

• The mean prevalence rate of CPV in Iran in 2018 was 24%. • There is a higher rate of prevalence and more intense symptoms of CPV-2 in dogs under 6 months. • The predominant variant of CPV in Iran is variant −2a. • The central part of Iran is the first infected region, specially Alborz province. • Original date of CPV proposed to be 1970. • The VP2 fragment of the CPV-2a variant in Iran is under positive selection pressure. Canine Parvo Virus 2 (CPV-2) culminated in lots of fatalities in domestic dogs since its emergence in 1978. Mainly, it is responsible for severe hemorrhagic diarrhea, vomiting, and dehydration. CPV-2 has three main variants known as 2a, 2b, and 2c. Due to the necessity of monitoring the evolutionary parameters of the virus, and also the lack of comprehensive study of CPV2 in Iran, this study is done for the first time in this country not only to characterize Iranian CPV genomes but also to study the evolutionary parameters and phylodynamics of CPV. The phylogenetic trees were constructed using the Maximum Likelihood (ML) method. By the use of the Bayesian Monte Carlo Markov Chain (BMCMC) method, evolutionary analysis and phylodynamics of the virus were investigated. Phylogenetic results showed that all Iranian isolates were classified in the CPV-2a variant. The central part of Iran was suggested to be the origin of the virus, especially the Alborz province. Before its prevalence throughout the country, the virus circulated in the central part, in Thran, Karaj, and Qom. Mutational analysis showed a positive selection pressure of CPV-2a. Investigating the evolutionary parameters of the virus proposed 1970 to be the date of birth of the virus, with a 95% credible interval between 1953 and 1987. The effective number of infections increased dramatically from 2012 to 2015, then faced a slightly decreasing trend from 2015 to 2019. A considerable up warding pattern was witnessed from the middle of 2019, which can be taken as a concern about the risk of vaccination failure. [ABSTRACT FROM AUTHOR]

The giant African snail Lissachatina fulica has been reported invading Cuba since 2014 and is now well established in areas of Havana and several nearby regions. This invasive species is of major concern to health authorities given its role as an important vector of parasites such as Angiostrongylus cantonensis , the causative agent of eosinophilic meningoencephalitis in humans. Here, we update the distribution within Cuba. We also report on our studies of experimental life-history traits to assess the population dynamics and potential for spread of this species in Cuba. The experimental population had a very low probability of dying at first age intervals (Type I survival curve) with a life expectancy of 71 weeks. During our experiment, sexual maturity was reached after 22 weeks (individuals of 70 mm shell length) and eggs were laid regularly (mean batch size: 188 ± 111.79 SD). We failed to detect any deviations from the mortality curve and individuals reached an average of 77.3 mm (shell length) and weighted 57.7 g after one year. Predicted curve models indicate that snails reaching their average lifespan of five years should attain 10–12 cm (shell length) and weight 160 g. The spreading of this invasive and vector snail has been tracked for four years in Cuba showing a steady increase of invaded localities. How fast and how far this species develops in Cuba is unknown but the life history parameters indicated in this paper show that it has a large potential to invade all areas of Cuba quickly unless a systematic abatement strategy is developed. [ABSTRACT FROM AUTHOR]

• Nineteen studies were identified that modelled S. japonicum control strategies. • Mathematical models of S. Japonicum have shifted towards the prevalence-based multi-host model. • Few mathematical models of S. Japonicum have considered other definitive hosts and seasonal fluctuations with mixed results. • Mathematical models have generally agreed on the inability of human treatment alone to reach elimination of S. Japonicum. • Few modelling studies have considered S. Japonicum in the Philippines. Schistosoma japonicum remains endemic in China and the Philippines. Substantial progress has been made in the control of Japonicum in both China and the Philippines. China is reaching elimination thanks to a concerted effort of control strategies. Mathematical modelling has been a key tool in the design of control strategies, in place of expensive randomised-controlled trials. We conducted a systematic review to investigate mathematical models of Japonicum control strategies in China and the Philippines. We conducted a systematic review on July 5, 2020, in four electronic bibliographic databases - PubMed, Web of Science, SCOPUS and Embase. Articles were screened for relevance and for meeting the inclusion criteria. Data extracted included authors, year of publication, year of data collection, setting and ecological context, objectives, control strategies, main findings, the form and content of the model including its background, type, representation of population dynamics, heterogeneity of hosts, simulation period, source of parameters, model validation and sensitivity analysis. Results After screening, 19 eligible papers were included in the systematic review. Seventeen considered control strategies in China and two in the Philippines. Two frameworks were identified; the mean-worm burden framework and the prevalence-based framework, the latter of which increasingly common. Most models considered human and bovine definitive hosts. There were mixed additional elements included in the models, such as alternative definitive hosts and the role of seasonality and weather. Models generally agreed upon the need for an integrated control strategy rather than reliance on mass drug administration alone to sustain reductions in prevalence. Mathematical modelling of Japonicum has converged from multiple approaches to modelling using the prevalence-based framework with human and bovine definitive hosts and find integrated control strategies to be most effective. Further research could investigate the role of other definitive hosts and model the effect of seasonal fluctuations in transmission. [ABSTRACT FROM AUTHOR]

• Develop and calibrate a mosquito population dynamics model with entomological and climate data. • Fit the population model to local mosquito trap data. • Demonstrate that trap data alone cannot quantify the actual mosquito population. • Develop a strategy to compare the mosquito population and rainfall impact among different areas. • Evaluate the vector control strategy in Miami-Dade County. Aedes aegypti is one of the most dominant mosquito species in the urban areas of Miami-Dade County, Florida, and is responsible for the local arbovirus transmissions. Since August 2016, mosquito traps have been placed throughout the county to improve surveillance and guide mosquito control and arbovirus outbreak response. In this paper, we develop a deterministic mosquito population model, estimate model parameters by using local entomological and temperature data, and use the model to calibrate the mosquito trap data from 2017 to 2019. We further use the model to compare the Ae. aegypti population and evaluate the impact of rainfall intensity in different urban built environments. Our results show that rainfall affects the breeding sites and the abundance of Ae. aegypti more significantly in tourist areas than in residential places. In addition, we apply the model to quantitatively assess the effectiveness of vector control strategies in Miami-Dade County. [ABSTRACT FROM AUTHOR]

Mosquitoes are responsible for the transmission of numerous serious pathogens. Members of the Aedes and Culex genera, which include many important vectors of mosquito-borne diseases, are highly invasive and adapted to man-made environments. They are spread around the world involuntarily by humans and are highly adapted to urbanized environments, where they are exposed to climate-related abundance drivers. We investigated Culicidae fauna in two urban parks in the city of São Paulo to analyze the correlations between climatic variables and the population dynamics of mosquitoes in these urban areas. Mosquitoes were collected monthly over one year, and sampling sufficiency was evaluated after morphological identification of the specimens. The average monthly temperature and accumulated rainfall for the collection month and previous month were used to explain climate-related abundance drivers for the six most abundant species ( Aedes aegypti, Aedes albopictus, Aedes fluviatilis, Aedes scapularis, Culex nigripalpus and Culex quinquefasciatus) and then analyzed using generalized linear statistical models and the Akaike Information Criteria corrected for small samples (AICc). The strength of evidence in favor of each model was evaluated using Akaike weights, and the explanatory model power was measured by McFadden's Pseudo-R 2 . Associations between climate and mosquito abundance were found in both parks, indicating that predictive models based on climate variables can provide important information on mosquito population dynamics. We also found that this association is species-dependent. Urbanization processes increase the abundance of a few mosquito species that are well adapted to man-made environments and some of which are important vectors of pathogens. Predictive models for abundance based on climate variables may help elucidate the population dynamics of urban mosquitoes and their impact on the risk of disease transmission, allowing better predictive scenarios to be developed and supporting the implementation of vector mosquito control strategies. [ABSTRACT FROM AUTHOR]

Visceral leishmaniasis is a significant public health problem in northwest Ethiopia, particularly in Kafta Humera district. The study was designed to determine the species composition and population dynamics of sand flies in five villages representing urban and semi-urban areas of Kafta Humera district namely, Setit Humera, Mykadra, Rawyan, Bereket and Adebay. Sand flies were collected for two to three nights monthly from May 2011 to April 2012 using CDC light-traps and sticky traps. Traps were placed in villages, at periphery of villages and farm fields. Sticky traps were also used for sampling indoor active sand flies. In total, 13,097 sand fly specimens of eight Phlebotomus species and 91,949 Sergentomyia specimens were collected. Among the Phlebotomus , P. orientalis was the predominant species (58.1%) followed by P. papatasi (29.6%), P. lesleyae (5.6%), P. bergeroti (3.8%), P. duboscqi (2.1%), P. alexandri (0.4%), P. heischi (0.2%) and P. rodhaini (0.2%). Significantly, higher number of P. orientalis was caught in Adebay village and the least in Setit Humera town. Seasonal abundance of P. orientalis increased during the dry season (January–May) and dropped drastically in the wet season (late June–September). Significant positive correlation was found between monthly abundance of P. orientalis and the monthly average air and surface soil temperature, while a negative correlation was found with monthly average rainfall and relative humidity. Higher number of P. orientalis was collected outdoors, especially in the farm fields followed by periphery of villages. Thus, various observations strongly suggested P. orientalis to be the principal vector in the study areas, where farm lands and periphery of villages were identified as the most risky habitats, whereas the indoors were the least ones. Appropriate control methods should be designed and implemented according to the knowledge of P. orientalis habitat preferences and seasonal dynamics in the district. [ABSTRACT FROM AUTHOR]

• Panstrongylus megistus is one of the primary species of epidemiological importance for Chagas disease transmission in Brazil. • P. megistus population dynamics is little studied; consequently, important genetic pattern such as genetic diversity and gene flow between environments have not yet been well characterized. • P. megistus has a long stay in the colonized environments, with rare dispersal to other locations. • Continuous entomological surveillance in the areas of occurrence of P. megistus is necessary to avoid the installation and formation of new foci of household infestation. Panstrongylus megistus is considered one of the primary species of epidemiological importance for the transmission of Chagas disease in Brazil due to its wide geographical distribution throughout the national territory, good ability to invade and colonize houses, and high rates of natural infection by the Trypanosoma cruzi. The importance of this species in Minas Gerais has been recognized since the 80s. It is responsible for the high prevalence rates of Chagas disease in the west of the state. Studies conducted in the municipality of Jaboticatubas show that P. megistus is still the most captured vector in the region, even after 40 years of uninterrupted actions of the Chagas Disease Control Program in the municipality. Despite the importance of the species, its population dynamics is little studied. Consequently, crucial genetic information such as genetic diversity and gene flow among environments have not been well characterized yet. In this context, this work presents a population genetic analysis at the microgeographic level using microsatellite markers in samples of P. megistus obtained from Jaboticatubas to better understand the infestation dynamics of the primary vector species of T. cruzi in the region. The observed and expected heterozygosity ranged from 0.26 to 0.47 and 0.47 to 0.65, respectively. Most loci presented Hardy-Weinberg disequilibrium due to the excess of homozygotes. The pairwise Fst ranged from 0.05 to 0.35, with the p value significant for all comparisons, indicating the absence of gene flow between them. The values of Fis found ranged from 0.25 to 0.52, all values of p ≤ 0.05, probably due to structured populations, inbreeding, or null alleles. The results suggest an extended stay of this species in the colonized environments, with rare dispersal to other locations. Such results differ from that observed for Triatoma brasiliensis and Triatoma dimidiata , species that present constant movement, even after colonization of the artificial environment, and are similar to the behavior of Triatoma infestans. Thus, the study reinforces the importance of continuous entomological surveillance in the areas of occurrence of P. megistus to avoid the installation and formation of new foci of household infestation in the region. [Display omitted] [ABSTRACT FROM AUTHOR]

The Asian tiger mosquito, Aedes albopictus (Skuse, 1895) is the anthropophilic and day-biter mosquito, residing in peridomestic habitats and is responsible for vector-borne diseases, i.e., chikungunya and dengue. The knowledge of mosquito life demographics is very important to provide a foundation for a successful vector control program. In the present study, a comparative adult life table, survival, and fecundity parameters were evaluated on desert (Jodhpur, Rajasthan) and coastal (Kolkata, West Bengal) strains of Aedes albopictus (Diptera: Culicidae) from India under the standard laboratory conditions. The results showed significant differences between these strains for the life expectancy of males, fecundity (total eggs/cohort and eggs/female life span), oviposition days, intrinsic rate of increase (r m), finite rate of increase (λ), and doubling time (DT). Female mosquitoes lived longer than the males in both strains. Significant differences were observed in the net reproductive rate (R 0) between Kolkata and Jodhpur strains. The coastal (Kolkata) strain showed a longer male life expectancy (5.6 days) than the desert strain (4.0 days). However, the fecundity (eggs/female lifespan) was higher in Kolkata (360.2) than the Jodhpur strain (229.7). The Kolkata strain showed higher R 0 , r m , λ , and the lower T, DT than the Jodhpur strain. Conclusively, the results indicate that the coastal strain of Ae. albopictus is more r-strategist than the desert strain. This study may help in the precise prediction of Ae. albopictus population dynamics surviving in these geographical areas for vector management. [ABSTRACT FROM AUTHOR]

• Differential distribution of triatomines is driven by geoclimatic conditions. • Three triatomine species are reported for the first time in Hidalgo state. • T. mexicana and T. gerstaeckeri , but not T. dimidiata , showed seasonal variation. • High infection rates with T. cruzi and domiciliation of triatomines were observed. • Temporal and spatial analyses are useful to identify potential high-risk sites. Triatomine vectors are responsible for the main route of transmission of the protozoan Trypanosoma cruzi , the etiological agent of Chagas disease. This illness is potentially life-threatening and highly disabling and represents a major public health concern in the endemic countries in Latin America. The analysis of the spatial and temporal occurrence of triatomine insects is critical, since control strategies strongly depend on the vector species found within each area. Such knowledge is non-existent in Hidalgo state, an endemic region of Chagas disease in Mexico. A Geographic Information System (GIS) was used to analyze broad-scale spatial and temporal patterns of synanthropic triatomines collected in Hidalgo. Data was taken from the Institute of Epidemiological Diagnosis and Reference (InDRE) of Mexico and the state program of Vector Control of the Secretary of Health, covering the period of 1997–2019. Our analyses demonstrate a differential distribution of Triatoma dimidiata, T. mexicana, T. gerstaeckeri and T. barberi , which are the four predominant species, and that climate, temperature, and precipitation are some of the drivers of their distribution pattern. Notably, we report the presence of T. nitida, T. pallidipennis and T. phyllosoma for the first time in the state. In addition, we found seasonal variations of the populations of T. mexicana and T. gerstaeckeri , but not for T. dimidiata , whose population remains constant throughout the year. The insects were found mainly intradomicile (81.79%), followed by peridomicile (17.56%) and non-domestic areas (0.65%), with an average T. cruzi infection of 16.4%. Based on this evidence, priority sites for vector control intervention were identified. Our findings are very valuable for understanding the epidemiology of Chagas disease, the generation of future potential risk maps and for the development and implementation of effective and targeted vector control programs in Hidalgo state. [Display omitted] [ABSTRACT FROM AUTHOR]

Chagas disease is the most important parasitic disease in Latin America. The causative agent, Trypanosoma cruzi , displays high genetic diversity and circulates in complex transmission cycles among domestic, peridomestic and sylvatic environments. In Ecuador, Rhodnius ecuadoriensis is known to be the major vector species implicated in T. cruzi transmission. However, across vast areas of Ecuador, little is known about T. cruzi genetic diversity in relation to different parasite transmission scenarios. Fifty-eight T. cruzi stocks from the central Ecuadorian coast, most of them derived from R. ecuadoriensis , were included in the study. All of them were genotyped as T. cruzi discrete typing unit I (DTU TcI). Analysis of 23 polymorphic microsatellite loci through neighbor joining and discriminant analysis of principal components yielded broadly congruent results and indicate genetic subdivision between sylvatic and peridomestic transmission cycles. However, both analyses also suggest that any barriers are imperfect and significant gene flow between parasite subpopulations in different habitats exists. Also consistent with moderate partition and residual gene flow between subpopulations, the fixation index ( F ST ) was significant, but of low magnitude. Finally, the lack of private alleles in the domestic/peridomestic transmission cycle suggests the sylvatic strains constitute the ancestral population. The T. cruzi population in the central Ecuadorian coast shows moderate tendency to subdivision according to transmission cycle. However, connectivity between cycles exists and the sylvatic T. cruzi population harbored by R. ecuadoriensis vectors appears to constitute a source from which the parasite invades human domiciles and their surroundings in this region. We discuss the implications these findings have for the planning, implementation and evaluation of local Chagas disease control interventions. [ABSTRACT FROM AUTHOR]

• Phlebotomus argentipes and Sergentomyia punjabensis were recorded from this area. • P. argentipes was the most common species. • Wind speed associated with lower sand fly abundance. • Rainfall associated with increased sand fly abundance. • High sand fly abundance lead to high disease prevalence. Sand flies are the primary vectors of leishmaniasis. Disease management with effective vector control depends on the knowledge of vector population dynamics. In Sri Lanka, despite few isolated entomological collections, long-term studies are not reported to date. In the reported study, monthly entomological surveillance was conducted from May 2017 to December 2018 in Polpithigama, Maho, and Galgamuwa Medical Officer of Health (MOH) areas using standard entomological techniques. Climatic data were collected from the Department of Meteorology, Sri Lanka. Patient records were collected from each MOH office. A total of 38,339 sand flies were collected. The majority were Phlebotomus argentipes (99.50%, n = 38,147), while the rest was Sergentomyia punjabensis (0.50%, n = 192). Wind speed reduces sand fly abundance (r = -0.519, P < 0.05) evidently by limiting the movement. Rainfall increases sand fly abundance (r = 0.842, P <0.05, lag = 6 months) probably by improving favorable conditions in breeding sites. The actual effect of humidity is not conclusive without further research. The observed higher prevalence of leishmaniasis in the study sites could be due to the higher sand fly density in these areas. The number of patients shows a strong positive correlation (r = 0.516, P <0.05) to the sand fly abundance with a lag of 7 months. Systematic surveillance of sand flies as a part of general healthcare services is strongly recommended to identify and prevent possible outbreaks through timely planned vector control measures. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to obtain updated information on mosquito diversity and malaria vector incrimination in Charsadda Khyber Pakhtunkhwa to help in devising effective control and preventive measures in the area. Monthly survey of indoor mosquitoes for one year was carried out in three villages, Dhaki Totaqi and Mathra. Female Anopheline were used to detect Circumsporozoites protein (CSP) using Enzyme Linked Immunosorbent Assay. Among 17 mosquito species, Culex quinquefasciatus, Anopheles splendidus, Anopheles stephensi, Anopheles fluviatilus, Anopheles culicifacies and Culex tritaeniorhynchus were predominant. Dhaki village had the highest mosquito species diversity (1.015) and similar species richness (0.7) and evenness (0.5) with village Mathra. Slide positivity rate (SPR) shows that the rate of malaria transmission increases with mosquito population. Four anopheline species i.e. A. stephensi, A. fluviatilis, A. splendidus , and A. culicifacies were CSP positiv e. The CSP rate was 0.8%, where two specimens of A. splendidus and one of A. fluviatilus were positive for Plasmodium falciparum, Plasmodium vivax was represented by two variants 210 and 247. Among the 20 CSP positive specimens, variant 210 was found in 12 (one belonging to A. culicifacies , two each of A. stephensi and A. fluviatilus , seven specimens of A. splendidus ) and 247 in 8 specimens (two of A. stephensi , three each of A. fluviatilus and A. splendidus ). The number of infected mosquitoes collected from animal sheds was higher (15) though non-significant ( P > 0.05) than that from bedrooms (8). [ABSTRACT FROM AUTHOR]

Suppression of Aedes albopictus populations is a substantial challenge for mosquito control programs globally because juveniles of this species are found in numerous kinds of domestic artificial containers that are difficult to detect, access, and eliminate. We conducted a multi-year assessment of the effect of different interventions to control Ae. albopictus near the northernmost geographic boundary of the species in temperate North America and deployed an array of BG-Sentinel traps for adult surveillance. Here we present the results of a comparative examination of adult sex ratios in urban and suburban areas, shifts in sex ratios after control interventions, and a discussion of the critical drivers of population dynamics of Ae. albopictus in our area. We collected significantly more male mosquitoes in urban as compared to suburban areas in June through September, but not in May (p<0.001). The higher number of male mosquitoes in urban areas could be attributed to a higher number of larval habitats within a closer proximity of the surveillance traps and the lower flight dispersal of males. Following application of adulticides in urban areas, Ae. albopictus male populations were reduced by 88% on average, which was higher than the 69% reduction in female populations. The higher reduction of male mosquitoes could be attributed to the smaller body mass of the males and their higher susceptibility to adulticides. The results of this study are directly relevant to the development of suitable control strategies that depend on manipulation of males, such as the sterile insect technique. The results could also be used to refine mosquito abatement by providing more accurate methods to determine the need and timing of vector control. [ABSTRACT FROM AUTHOR]

• Sites of human schistosome transmission are commonly invaded by aquatic plants. • Experimental plant invasions reduce algae, a key food for snails and schistosomes. • As predicted, Water hyacinth invasion suppressed snail populations. • In contrast, water lettuce invasion caused snail populations to increase. • Invasive plant traits could inform management for environment and human health. Vectors and intermediate hosts of globally impactful human parasites are sensitive to changes in the ecological communities in which they are embedded. Sites of endemic transmission of human schistosome can also be invaded by nonnative species, especially aquatic plants (macrophytes). We tested the effects on macrophyte invasions on experiment snail and schistosome populations created in 100 L mesocosm tanks. We established macrophyte-free mesocosms and those containing one of four widespread macrophyte species that are inedible to snails (duckweed, hornwort, water lettuce, or water hyacinth) and then tracked edible resources (periphyton algae) and the abundance, reproduction, and infection of snail intermediate hosts for 16 weeks. We predicted that the three floating macrophytes would reduce periphyton, thereby reducing snail reproduction, abundance, and infections. In contrast, we predicted that hornwort, which is submerged and provides substrate for periphyton growth, would increase snail reproduction and abundance. As predicted, all floating macrophytes decreased periphyton, but only water hyacinth significantly decreased snail reproduction and abundance. Snail abundance increased significantly only with water lettuce. We hypothesize that this unanticipated increase in snails occurred because water lettuce produced abundant and/or high quality detritus, subsidizing snails despite low periphyton availability. Unfortunately, we detected too few infections to analyze. Aquatic macrophytes exert strong species-specific effects on snail populations. Therefore, efforts to manage invasive plants in endemic sites should evaluate changes in resources, snails, and transmission potential. We recommend caution with management efforts that produce large amounts of detritus, which might stimulate snail populations and therefore risk of human exposure. [ABSTRACT FROM AUTHOR]

Abstract: The hypothetical impact of aerial spraying on tsetse fly populations is investigated. Spray cycles are scheduled at intervals two days short of the first interlarval period and halted once the last of the female flies that originated from pre-spray-deposited pupae have been sprayed twice. The effect of temperature on the aerial spraying of tsetse, through its reproductive cycle and general population dynamics, is of particular interest, given that cooler weather is preferred for the settling of insecticidal droplets. Spray efficacy is found to come at a price due to the greater number of cycles necessitated by cooler weather. The extra cost is argued to be worth while. Pupae, still in the ground at the end of spraying, are identified as the main threat to a successful operation. They are slightly more vulnerable at the low temperature extreme of tsetse habitat (16°C), when the cumulative, natural pupal mortality is high. One can otherwise base one''s expectations on the closeness with which the time to the third last spray approaches one puparial duration. A disparity of anything close to the length of a spray cycle advocates caution, whereas one which comes close to vanishing should be interpreted as being auspicious. Three such key temperatures, just below which one can anticipate an improved outcome and just above which caution should be exercised, are 17.146°C, 19.278°C and 23.645°C. A refinement of the existing formulae for the puparial duration and the first interlarval period might be prudent in the South African context of a sympatric Glossina brevipalpis–Glossina austeni, tsetse population. The resulting aerial spraying strategy would then be formulated using a G. brevipalpis puparial duration and a G. austeni first interlarval period. [Copyright &y& Elsevier]

Abstract: A 2-year survey was carried out from May to November 2008 and 2009 to study the sand fly species composition, its seasonal phenology and density in Apulia region (southern, Italy). The study was conducted in a dog shelter located in a new residential urban district where Leishmania infantum is endemic. Sand flies were collected using sticky traps from May to November, at about 7-day intervals. Temperature and relative humidity were recorded daily. In December 2008, general environmental improvements (e.g., the ground was covered with gravel and the vegetation present inside the cages was removed to facilitate cleaning) were made in the study area. The most diffused species during the whole study period were Phlebotomus perniciosus (2008, n =248, 49.4%; 2009, n =254, 50.6%) followed by Phlebotomus neglectus (2008, n =76, 39.8%; 2009, n =115, 60.2%) and Phlebotomus papatasi (2008, n =5, 50.0%; 2009, n =5, 50.0%). Four specimens of Phlebotomus perfiliewi were collected only in the first year. The number of Sergentomyia minuta specimens collected increased considerably in the second (n =548, 86.2%) in comparison to the first year (n =88, 13.8%). The highest number of phlebotomine sand flies was collected in July and August when a mean temperature from 27.09 to 28.02°C and mean relative humidity from 47.28 to 56.36% were recorded. The variations in phlebotomine sand fly species diversity and abundance recorded in this study were related to climatic and environmental factors. Data here presented confirm that sand flies easily adapt to the urban environments and that the may represent a public health concern for L. infantum and other pathogen transmission also in similar urban environment of southern Europe. [ABSTRACT FROM AUTHOR]

Human leptospirosis (Leptospira spp. infection) is a worldwide public health problem that is of greatest concern for humid tropical and subtropical regions. The magnitude of the problem in these areas is larger because of the climatic and environmental conditions the bacterium face outside their hosts but also because of the frequency of contacts between people and sources of infection. Rodents are thought to play the most important role in the transmission of human leptospirosis. We here model the dynamics of infection in an African rodent (Mastomys natalensis) that is thought to be the principal source of infection in parts of Tanzania. Our model, representing the climatic conditions in central Tanzania, suggests a strong seasonality in the force of infection on humans with a peak in the abundance of infectious mice between January and April in agricultural environments. In urban areas the dynamics are predicted to be more stable and the period of high numbers of infectious animals runs from February to July. Our results indicate that removal of animals by trapping rather than reducing the suitability of the environment for rodents will have the greater impact on reducing human cases of leptospirosis. [Copyright &y& Elsevier]

Abstract: Triatoma infestans, the main vector of Chagas disease in Southern Cone countries, frequently infests peridomestic structures housing domestic animals. A total of 814 T. infestans collected from 35 different peridomestic sites in rural northwestern Argentina over 1–4 consecutive seasons was examined for recent blood meals and nutritional status. Bugs from goat or pig corrals had lower qualitative nutritional status and mean weight to length ratios (W/L) than those captured in chicken coops. Males systematically had lower qualitative nutritional status and W/L than females. Using logistic multiple regression, the daily feeding rates of T. infestans were significantly associated with season and stage but not ecotope, whereas the proportion of well-fed bugs varied significantly with all three factors. The seasonal trends in feeding rates and nutritional status were consistent with the local availability and breeding timing of domestic animals. The observed data fed into an empirical model predicted that the probability of flight initiation would peak in summer from pig or goat corrals, not chicken coops, and be insignificant in all ecotopes in spring and fall. Male T. infestans outnumbered females as potential fliers. This is the first study conducted in well-defined habitat units that shows significant heterogeneities in the feeding rates and nutritional status of triatomine populations linked to host demographics and management, and how these affect flight dispersal potential over seasons. Peridomestic bug populations are of great relevance as a source of domestic reinfestation and for the elimination of T. infestans. [Copyright &y& Elsevier]

The population dynamics of the larval and adult life stages of the malaria vector Anopheles gambiae Giles were studied in Miwani, western Kenya, in relation to meteorological conditions. Larval density within a habitat, the number of larval habitats and sibling species composition were investigated as determinants of larval population dynamics. Female vector densities inside local houses and sibling species composition were investigated as determinants of adult population dynamics.Larval densities were estimated using a modified area-sampling method. Within the habitats, all instars showed a highly aggregated distribution, with the exception of second instars. A longitudinal study on the larval populations of A. gambiae s.l. in two different types of habitat (dirt track and ditch) was carried out, using a novel sampling procedure. A. gambiae s.s. and Anopheles arabiensis, the two sibling species occurring sympatrically in the study area, showed some spatial segregation between the two types of habitat. Rainfall was significantly correlated with the number of A. gambiae s.l. larval habitats during the first 6 weeks of study taking 1 week time lag into account, while over the entire 5-month study period correlations were less clear. With 1 week time lag, rainfall was also significantly correlated with the number of female A. gambiae s.l. collected from CDC-light traps in the study houses. Both larval and adult populations showed a significant increase in the proportion of A. gambiae s.s. within the mixed population of A. gambiae s.s. and A. arabiensis over time. Although not significantly correlated, the ratio of rainfall over precipitation/potential evapotranspiration (P/PE), indicative of the humidity conditions in the area, was probably the driving force of this increase. [Copyright &y& Elsevier]

Our objectives were to describe and compare the seasonal variations in microclimatic conditions in domestic and peridomestic ecotopes infested by Triatoma infestans, the main vector of Chagas disease, in rural northwestern Argentina. Using data loggers for 4–7 consecutive days in October 2000, February, May and August 2001, microsite (interior of thatched roofs) and ambient temperatures or relative humidity (RH) were recorded simultaneously and compared with an external reference. The damping effects on microsite temperature and ambient RH increased successively from the goat corral to the chicken coop or pig corral, to the storeroom or human habitation. In the interior of the thatched roofs of the habitation and storeroom, average external minima were increased by +5.0 to +5.6 °C in all seasons, and average external maxima were decreased by −4.3 to −5.6 °C in October–May and −10.6 °C in August. On average, the human habitation damped extreme temperatures by 8 °C over a wider range than previously reported. The interior of the thatched roofs of the pig corral and chicken coop exerted intermediate damping effects that varied over seasons, whereas the goat corral''s thatch showed little or no damping effects at all. The adobe-and-thatch habitation and storeroom presented nearly optimal and more suitable conditions for T. infestans populations than other open structures housing animals. Global climate changes are expected to affect peridomestic populations of T. infestans much more than domestic bug populations, provided other local conditions are held constant. Heterogeneous habitat conditions are expected to affect T. infestans population parameters, dispersal, control and infection with Trypanosoma cruzi. [Copyright &y& Elsevier]

• There is a co-existence of new housing and traditional housing in the study area. • Patches of all qualities were occupied by Triatoma infestans. • Triatoma infestans occupancy was similar in brand new and traditional dwellings. • New housing construction alone was not enough to decrease the vector occupancy. Triatoma infestans (Hemiptera: Reduviidae) is a hematophagous insect, vector of the parasite Trypanosoma cruzi, etiological agent of the Chagas disease. In the south of La Rioja, Argentina, the persistent infestation by triatomines encouraged a program of construction of brand new dwellings in rural areas since 2008, to reduce infestation. According to the metapopulation theory approach, each dwelling was considered to be a patch with different degrees of quality concerning the availability of shelters for T. infestans. Accordingly, brand new dwellings (BNDs) are considered of lower quality for triatomines, compared to traditional dwellings (TDs). The main objective of this study was to analyse the occupancy in patches of different quality and to evaluate the effect of BNDs in the control of T. infestans. 397 patches from three departments of the southern part of La Rioja province were analysed during the period from 2014 to 2017. Six samplings were carried out to estimate the occupancy by T. infestans in patches assigned with different qualities. During the studied period, changes in the occupancy status of the patches among samplings were recorded, and the metapopulation variables which affect the occupancy of T. infestans were analysed. The results showed that all patches, even those considered of lower quality and smaller size, were occupied by T. infestans in a range from 3.8% to 25.5%. In general, the probability of T. infestans occupancy among samplings showed no difference among all studied patches. The occupancy of patches by T. infestans was associated with "department", "number of patches" and "number of positive patches in the radius of 400 m" (analysis GEE models). However, "patch quality", "size", and "distance" showed no effect on T. infestans occupancy. 44.1% of patches with BND were occupied at least once during the study period. Some of these showed "persistent occupancy" by T. infestans. No differences in the T. infestans occupancy between BNDs and TDs were observed. These results allowed us to analyse the impact of the new housing construction as a vector control measure in the metapopulation context of La Rioja province. Rethinking the old hypothesis that new housing construction has an impact on the vector control of Triatoma infestans : A Metapopulation Analysis. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Landfill garbage is main source of several serious diseases. • Landfill garbage attracts a lot of insect pests. • Insect population in garbage is dominated by Dipterans. • Insect diversity and density fluctuate with the season. • People around the garbage get more infectious diseases. The landfill garbage includes organic and inorganic matter. The organic matter covers more than 50% of the total waste material. Due to improper management of landfill garbage, it causes serious risks to human health directly by the emission of toxic gasses. On the other hand, landfill sites are the natural habitat of several microbes and arthropods. The present discussion illustrates the impact of landfill garbage on insect ecology and human health. Here, we highlighted the arthropod density as well as diversity. Moreover, the population of insect vectors of various diseases, insect scavengers as well as pollinators has been pinpointed. It shows that landfill sites and adjacent areas are hotspots for a wide variety of arthropods. The proper management of landfill sites could reduce the population dynamics of various insect pests, and health risks could be decreased in low-and middle-income countries. [ABSTRACT FROM AUTHOR]

• Monthly collection of adult S. chumpornense revealed abundance peak in dry season. • Infectious stage of the Leucocytozoon was detected in S. chumpornense female. • Genetically similar Leucocytozoon found in domestic chickens and S. chumpornense. The black fly, Simulium chumpornense Takaoka & Kuvangkadilok, is suspected to be a natural vector of Leucocytozoon. In this study, seasonal variation in abundance of the adult fly and molecular detection of Leucocytozoon in S. chumpornense and in domestic chicken was investigated in northeastern Thailand. A total of 10,416 female adults were obtained by monthly collection for one year at six sampling sites. There was a peak of abundance in the dry season (March – May) when more than 74% of the specimens were collected. An increased number of suitable habitats for immature stages during the dry season is potentially a factor driving dry season abundance. Molecular genetic investigations revealed that S. chumpornense harbored the infectious stage of Leucocytozoon sp. indicating that it is a natural vector of this parasite. Blood smear screening for the parasite in domestic chickens found a considerable prevalence (52%) of Leucocytozoon spp. infections. The cytochrome b sequences of this parasite in domestic chickens comprised two lineages. One lineage was closely related to Leucocytozoon sp. found in S. chumpornense and another matched with L. schoutedeni. Therefore, S. chumpornense is a vector of Leucocytozoon sp. while L. schoutedeni is possibly transmitted by other ornithophilic black fly species. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Vector indices are often poor predictors of geographic disease risk. • When longitudinal vector surveillance data is available, vector population dynamics parameters can be estimated. • Vector population dynamics are investigated as a measure of disease risk. • In this work we have shown that mosquito intrinsic growth rate has a larger predictive accuracy for dengue incidence than mosquito abundance. • In the light of this result we encourage vector surveillance and control agencies/scientist to explore the use of intrinsic growth rate as index for disease risk. Understanding geographic population dynamics of mosquitoes is an essential requirement for estimating the risk of mosquito-borne disease transmission and geographically targeted interventions. However, the use of population dynamics measures, such as the intrinsic growth rate, as predictors in spatio-temporal point processes has not been investigated before. In this work we compared the predictive accuracy of four spatio-temporal log-Gaussian Cox models: (i) With no predictors; (ii) mosquito abundance as predictor; (iii) intrinsic growth rate as predictor; (iv) intrinsic growth rate and mosquito abundance as predictors. This analysis is based on Aedes aegypti mosquito surveillance and human dengue data obtained from the urban area of Caratinga, Brazil. We used a statistical Moran Curve approach to estimate the intrinsic growth rate and a zero inflated Poisson kriging model for estimating mosquito abundance at locations of dengue cases. The incidence of dengue cases was positively associated with mosquito intrinsic growth rate and this model outperformed, in terms of predictive accuracy, the abundance and the null models. The latter includes only the spatio-temporal random effect but no predictors. In the light of these results we suggest that the intrinsic growth rate should be investigated further as a potential tool for predicting the risk of dengue transmission and targeting health interventions for vector-borne diseases. [ABSTRACT FROM AUTHOR]

• P argentipes , the vector species of leishmaniasis was the predominant sand fly species prevailed throughout the year in the study population. • Maximum vector density was recorded during the month of April to September. • Atmospheric temperature was the most important predictor for vector density along with humidity and rainfall. • The presence of outdoor populations of the vector sand fly is very important as they are not exposed to insecticide treated wall used for control. Vector control is one of the main aspects to reach the target of eliminating visceral leishmaniasis from Indian sub-continent as set by the World Health Organisation. Data on different aspects of vector like ecology, behaviour, population dynamics and their association with environmental factors are very important for formulating an effective vector control strategy. The present work was designed to study the species abundance and impact of environmental factors on population dynamics of vector P. argentipes in a visceral leishmaniasis endemic area of Malda district, West Bengal. Adult sand flies were collected using light traps and mouth aspirators from twelve kala-azar affected villages of Habibpur block of Malda district, on a monthly basis from January to December, 2018. Morphological and molecular methods were used for species identification. Population dynamics were assessed by man hour density and per night per trap collection. Data were analysed using SPSS software to determine the impact of environmental factors on vector population P. argentipes was found to the predominant species and prevalent throughout the year. A significantly higher number of sand flies were collected from cattle sheds than human dwellings and peri-domestic vegetation. A portion of the P. argentipes population was exophilic and exophagic as evidenced by their collection from peri-domestic vegetation. The highest population density was recorded during April to September. Population dynamics were mostly influenced by average temperature along humidity and rain fall. Resting behaviour of sand flies was not restricted to the lower portion of the wall but equally distributed throughout the wall and ceiling. Programme officials should consider management of outdoor populations of the sand flies and timings of indoor residual spray for chemical control purpose. [ABSTRACT FROM AUTHOR]

• We developed a stage-structured population dynamics model for Aedes albopictus. • The model includes temperature-dependent biodemographic functions. • We predict Ae. albopictus potential distribution, abundance and activity in the EU. The Asian tiger mosquito (Aedes albopictus) is one of the most invasive disease vectors worldwide. The species is a competent vector of dengue, chikungunya, Zika viruses and other severe parasites and pathogens threatening human health. The capacity of this mosquito to colonize and establish in new areas (including temperate regions) is enhanced by its ability of producing diapausing eggs that survive relatively cold winters. The main drivers of population dynamics for this mosquito are water and air temperature and photoperiod. In this paper, we present a mechanistic model that predicts the potential distribution, abundance and activity of Asian tiger mosquito in Europe. The model includes a comprehensive description of: i) the individual life-history strategies, including diapause, ii) the influence of weather-driven individual physiological responses on population dynamics and iii) the density-dependent regulation of larval mortality rate. The model is calibrated using field data from several locations along an altitudinal gradient in the Italian Alps, which enabled accurate prediction of cold temperature effects on population abundance, including identification of conditions that prevent overwintering of the species. Model predictions are consistent with the most updated information on species' presence and absence. Predicted population abundance shows a clear south-north decreasing gradient. A similar yet less evident pattern in the activity of the species is also predicted. The model represents a valuable tool for the development of strategies aimed at the management of Ae. albopictus and for the implementation of effective control measures against vector-borne diseases in Europe. [ABSTRACT FROM AUTHOR]